Abstract
It has been found that the oxidation of thiamine by cyanogen bromide (BrCN) under alkaline condition produces a new fluorescent compound, O-carbamoylthiochrome (Carb-Thc), as well as thiochrome (Thc). The structure of Carb-Thc was determined by its spectral data and comparison with an authentic sample of this compound derived from O-carbamoylthiamine. Carb-Thc was characterized from the UV spectrum and fluorescence spectrum in comparison with those of Thc. The spectroscopic features of both compounds were essentially identical. These observations suggest that assay of thiamine by BrCN-NaOH method is not disturbed by contamination of Carb-Thc which may be formed as a by-product in the assay process. Amounts of Thc and Carb-Thc produced under several reaction conditions were determined.
